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Whereas the ultimate world supply of minerals is controlled by geological factors, the actual supply at any particular time is controlled by economic factors. Mineral production is a function of investment in exploration, mining, and processing - and research in these fields. Given the long lead time between a decision to explore and actual production from any deposit found, the increasing difficulty of finding deposits in the well prospected parts of the world, the political barriers to exploration in the less developed countries, the energy barriers to mining and processing ever lower grade ores, and the lengthy time required to develop new exploration, extraction, and processing techniques, adjustments in supply in response to changes in demand cannot be assumed to be automatic.  相似文献   
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Australia is one of the world's main producers and exporters of both fuel and non-fuel minerals. Among the main commodities produced for export are bauxite/alumina, iron ore, and nickel—Australia is also an increasingly important source of supply of black coal, especially for Japan, and is a significant producer and exporter of a number of base metals. Resources are adequate to support a substantial expansion of both non-oil fuels and other minerals. The potential for growth, both in terms of specific commodities and in the overall role of Australia in the world mineral industry, will depend to a very large extent on the cost competitiveness of Australian mining and on continuing inflow of capital.  相似文献   
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Western mine production of gold has been declining in the past five years — at the same time as the price of gold has risen dramatically. Predictions of a continued high demand for gold and the current US interest in adopting some form of ‘gold standard’ have focused attention on the supply of new gold. This paper discusses the structure of gold supply and demand, the present pattern of production of new gold and the possible effect of future price changes on Western gold mine production in the 1980s.  相似文献   
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Mineral reserves are unevenly and erratically distributed throughout the world; those countries which were intensively explored in the past — the USA, Canada, the USSR, Australia, South Africa, and a limited number of Asian, African, and Latin American countries — control a large share of many of the industrially important metallic minerals. Current attitudes towards exploration and the mining industry in both the developed and the less developed countries should clearly encourage rather than discourage new exploration. Given an increase in exploration, new reserves may well be found in previously unexplored areas, but any major increase in world mineral supplies will probably come from mining very low- grade deposits and developing new methods of mining and processing non-conventional ores. While it is vital to increase research and development in exploration techniques and mining and processing technology, it is also critical to maintain current levels of consumption and trade by reversing the trend towards trade restriction on the part of some of the less developed countries who are important mineral exporters.  相似文献   
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The distinction between an exploitable and a non-exploitable mineral deposit is dynamic, varying as a function of changing economic and technological factors. A conceptual framework is proposed: ‘reserves’ are restricted to known currently exploitable deposits; ‘known resources’ are reserves plus currently non-exploitable deposits; ‘total resources’ are known resources plus all deposits not yet discovered. The short-term inadequacy of some mineral reserves requites a policy of accelerated mineral exploration and rapid development of new exploration techniques. Future problems could be avoided if the nature of resources is recognized and new mineral extraction and processing techniques for lower grade and unconventional mineral deposits are developed.  相似文献   
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